Toronto roads will be swept for bombs, a dummy car will be used to distract from U.S. President Barack Obama's location, and at least five countries have demanded motorcades with at least 35 cars.
For a city accustomed to the hair-pulling frustration of traffic, the G20 is expected to bring a whole new dimension to the concept of gridlock.
"The key is to try and minimize the impact for the rest of the city, because as much as we want to say it's business as usual, it really isn't," said traffic services Sergeant Tim Burrows.
The summit may be held to discuss global finances, but its most immediate impact will be on city traffic – from road closings to motorcades and security perimeters.
On the day Toronto was named as host city for the meeting of G20 leaders, a traffic management team was put in place. Next week, an operations room will be set up in police headquarters to monitor traffic, while a team of officers from the Integrated Security Unit will man the Major Incident Command Centre, keeping an eye out for protests or accidents that could further complicate things on city roads.
The Catholic and public school boards cancelled school buses on Friday in anticipation of traffic jams, and Toronto police have announced a raft of road closings from Highway 427 to Front Street.
The roads will be jammed with cars transporting dignitaries, bureaucrats and police between Toronto and Huntsville, the site of the G8 meeting. To facilitate their travel needs, the government placed a public tender for 52 deluxe motor coaches, 24 passenger buses, 70 passenger vans, 12 sedans, and 55 cargo vans. The RCMP and OPP will be busing in 4,000 officers to Huntsville, while 5,600 officers will have to be transported to Toronto for the G20.
Already, the fences have created major congestion during rush hour. Bay Street has been at a standstill most mornings, cars have been towed en masse to facilitate security construction and at least one driver has collided with the concrete barrier surrounding the Metro Toronto Convention Centre.
"If people are having a hard time navigating the fence line, those aren't the people we want on our roads to begin with," Sergeant Burrows said.
He said more traffic restrictions will be announced as the summit dates approach, and that the impact will be felt more profoundly by drivers who try to enter the downtown core.
While Toronto police try to keep city streets moving, the RCMP will be transporting the VIPs. Leader motorcades will be driven by suit-wearing and specially trained officers, most of whom are being brought in from jurisdictions like Ottawa and Peel – which holds jurisdiction over Pearson International Airport – who are used to dealing with motorcades.
Sam Schwartz, the former deputy commissioner of New York City Transportation, who is known as Gridlock Sam, said it's not unusual for traffic to come to a complete standstill, and for motorists to turn off their engines, when dignitaries are ferried around Manhattan.
Security personnel for each head of state will make their own demands to the RCMP and CSIS, he said.
"Everybody will say they need more than any city's willing to give them," he said. "Each country believes they are more important than the other country. Maybe it's a phallic symbol, but they measure it by the size of their motorcade."
Some heads of state require city officials to actually freeze their routes, which means not even pedestrians are allowed to cross.
"Heads of state are used to being treated as the boss, and they may decide that they want to go shop on Yonge Street and there's little you can do about it,' he said.
In the United States, Mr. Obama travels in a motorcade of more than 30 cars, including a dummy car, and the roads he travels are swept for bombs before he uses them.
"I would imagine the Secret Service would make a similar request when he's in Canada," Mr. Schwartz said.
When multiple leaders are in town, police must the establish a priority of motorcades, meaning one leader must sometimes wait. In the U.S., Mr. Schwartz said it is not unusual for the State Department to receive complaints from foreign dignitaries about how their motorcade was treated.
In Toronto, Sergeant Burrows expects most complaints will come from the general public.
"A lot of people will sit there and yell at you when you close a road," he said. "People see it as a personal inconvenience, but it's a little bit bigger than that."